Mode field radius measurements in single‐mode fibers by nfp technique

Abstract

AbstractThere are various methods for measuring the mode field radius in single‐mode fibers. However, measurement accuracy of the methods has not been reported yet. This paper describes the error factors for the mode field radius measurement by NFP technique to improve the accuracy of this technique. The input optical (10) sensitivity of the infrared (IR) vidicon camera is investigated which affects the precision of the NFP technique. As a result, the nonlinearity and shading distribution of the IR vidicon camera are clarified. Moreover, error factors for the technique are investigated. On the basis of investigation, the measurement conditions for this technique to obtain high accuracy are specified. The mode field radius of various types of fibers is increased under these conditions. As a result, measurement of the mode field radius became possible with reproduction error of less than 0.1 μm.